Washing machine

ABSTRACT

A washing machine having a rotor directly connected to a rotary shaft. The driving motor includes a stator mounted to an outer surface of a water tub, and a rotor disposed around the stator while being directly connected to the rotary shaft, which is connected to a rotary tub. An insertion hole is formed at a center of the rotor, and a plurality of fitting holes are formed around the insertion hole. At an end of the rotary shaft is formed an inserting protrusion, which corresponds to the insertion hole. The rotor is fixed to the rotary shaft by inserting the inserting protrusion through the insertion hole. To the rotor is attached a reinforcing member having a plurality of fitting protrusions, which vertically extend such that the fitting protrusions are fitted into the fitting holes of the rotor, respectively, such that the strength of the rotor is increased.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of Korean Patent Application No. 2004-76577, filed on Sep. 23, 2004 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

Apparatuses consistent with the present invention relate to a washing machine, and, more particularly, to a washing machine having an improved fixing structure between a rotary shaft and a rotor of a driving motor, whereby the rotor is easily and quickly fixed to the rotary shaft.

2. Description of the Related Art

When laundry is washed by a washing machine, a rotary tub is rotated in alternating directions. When the washed laundry is dewatered by the washing machine, on the other hand, the rotary tub is rotated only in one direction at a high speed. Consequently, the rotary tub is rotatably disposed in a water tub, in which wash water is filled, and at the outside of the water tub is disposed a driving motor to rotate the rotary tub.

A washing machine is disclosed in U.S. Pat. No. 6,510,716, which provides a water tub; a rotary tub rotatably disposed in the water tub while being attached to a rotary shaft extending through the water tub for washing the laundry; and a driving motor disposed at the outside of the water tub for rotating the rotary shaft and the rotary tub.

The driving motor includes a stator mounted to an outer surface of the water tub; and a rotor disposed around the stator while being connected to the rotary shaft. In an opening formed at the center of the rotor is disposed a connection member connected between the rotor and the rotary shaft for transmitting a rotating force of the rotor to the rotary shaft.

In the washing machine disclosed in the above-mentioned patent, however, the structure of the connection member is very complicated such that the rotary shaft is connected to the rotary tub with a coupling force necessary for the rotor to effectively rotate the rotary shaft and the rotary tub. Also, the connection member is fixed to the rotor by a plurality of bolts, which increases the manufacturing costs of the connection member and time necessary to assemble the connection member.

Furthermore, the rotary shaft is not directly connected to the rotor, i.e., the rotary shaft is connected to the rotor via the connection member. As a result, it is difficult to coaxially fix the rotor to the rotary shaft, and therefore, noise and vibration due to eccentricity between the rotor and the rotary shaft are generated when the rotor and the rotary shaft are rotated.

SUMMARY OF THE INVENTION

Therefore, it is an exemplary aspect of the invention to provide a washing machine having a structure in which a rotor of a driving motor is directly connected to a rotary shaft.

It is another exemplary aspect of the invention to provide a washing machine that is capable of increasing the strength of the rotor of the driving motor with a simple structure.

In accordance with one aspect, the present invention provides a washing machine comprising: a water tub; a rotary tub disposed in the water tub; a rotary shaft mounted to the rotary tub and extending through the water tub; a rotor directly connected to the end of the rotary shaft; and a reinforcing member attached to the rotor to increase the strength of the rotor.

The rotor may have a polygonal insertion hole, and the rotary shaft may have a polygonal inserting protrusion formed at the end thereof, the inserting protrusion of the rotary shaft being inserted through the insertion hole of the rotor. The reinforcing member may also have a polygonal through-hole corresponding to the insertion hole of the rotor, the inserting protrusion of the rotary shaft being inserted through the through-hole of the reinforcing member. The reinforcing member also has a plurality of fitting protrusions extending vertically from the reinforcing member, and the rotor has a plurality of fitting holes, into which the fitting protrusions of the reinforcing member are fitted, respectively, such that the reinforcing member is easily attached to the rotor.

An exemplary embodiment of the washing machine comprises: a fixing bolt threadly coupled to the inserting protrusion of the rotary shaft through the reinforcing member and the rotor from the outside of rotor. Further, the washing machine may comprise a pad disposed between the reinforcing member and a head of the fixing bolt.

Additional aspects and/or features of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Aspects and features of the invention will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings, of which:

FIG. 1 is a longitudinal sectional view showing a washing machine according to an exemplary embodiment of the present invention;

FIG. 2 is an enlarged sectional view showing a rotary shaft connected to a rotary tub and a driving motor to rotate the rotary shaft;

FIG. 3 is an exploded perspective view showing the fixing structure between a rotor of the driving motor and the rotary shaft;

FIG. 4 is an assembled perspective view of FIG. 3; and

FIG. 5 is a sectional view taken along the line V-V of FIG. 4.

DETAILED DESCRIPTION OF EXEMPLARY, NON-LIMITING EMBODIMENTS OF THE INVENTION

Reference will now be made in detail to exemplary embodiments of the present invention. The embodiments described below explain the present invention with reference to the figures.

FIG. 1 is a longitudinal sectional view showing a washing machine according to an exemplary embodiment the present invention, and FIG. 2 is an enlarged sectional view showing a rotary shaft connected to a rotary tub and a driving motor to rotate the rotary shaft.

As shown in FIG. 1, the washing machine comprises a housing 10 forming the appearance of the washing machine; a water tub 11 disposed in the housing 10 for storing wash water; a rotary tub 12 rotatably disposed in the water tub 11 for washing laundry; and a door 13 hingedly attached to the front surface of the housing 10.

At the upper part of the housing 10 are disposed a water supply hose 14 to supply wash water to the water tub 11 and a detergent supply unit 15 to supply detergent to the water tub 11. At the lower part of the housing 10 are disposed a drain hose 16 and a drain pump 17 to discharge wash water in the water tub 11 out of the housing 10.

At the outside of the water tub 11 is disposed a driving motor 30 to rotate the rotary tub 12 in alternating directions. Between the rotary tub 12 and the driving motor 30 is disposed a rotary shaft 20, having one end connected to the rotary tub 12 and the other end connected to the driving motor 30, to transmit a rotating force of the driving motor 30 to the rotary tub 12. The rotary shaft 20 extends through the water tub 11.

As shown in FIG. 2, the driving motor 30 comprises a stator 31 having a ring-shaped magnetic core 32 attached to the outer surface of the water tub 11 and a coil 33 wound on the magnetic core 32; and a rotor 40 disposed around the stator 31 while being connected to the rotary shaft 20. The rotary shaft 20, having one end connected to the rotary tub 12 and the other end connected to the rotor 40, is supported by bearing members 22 disposed at the water tub 11.

The fixing structure between the rotary shaft 20 and the rotor 40 will be described hereinafter with reference to FIGS. 3 to 5.

FIG. 3 is an exploded perspective view showing the fixing structure between the rotor 40 of the driving motor 30 and the rotary shaft 20, FIG. 4 is an assembled perspective view of FIG. 3, and FIG. 5 is a sectional view taken along the line V-V of FIG. 4.

As shown in FIG. 3, the rotor 40 comprises a disk-shaped base 41, to which the rotary shaft 20 is connected; an outer circumferential extension 42 vertically extending from a rim of the base 41; and a plurality of magnets 43 attached to the outer circumferential extension 42 while being spaced a predetermined distance from each other.

At the center of the base 41 of the rotor 40 is formed an insertion hole 44, through which the rotary shaft is inserted. Around the insertion hole 44 are disposed a plurality of rotary blades 45 and heat sink holes 46 in the radial direction thereof while the rotary blades 45 and the heat sink holes 46 are alternately arranged in the circumferential direction thereof.

At the end of the rotary shaft 20 is integrally formed an inserting protrusion 21, which has the same shape and size as the insertion hole 44 such that the inserting protrusion 21 is inserted through the insertion hole 44 of the base 41.

Preferably, but not necessarily, the insertion hole 44 and the inserting protrusion 21 are formed in the shape of a polygon such that the rotary shaft 20 can be rotated along with the rotor 40 when the rotor 40 is rotated after the inserting protrusion 21 is inserted through the insertion hole 44, i.e., such that the rotor is prevented from rotating relative to the rotary shaft. In this embodiment, the insertion hole 44 and the inserting protrusion 21 are approximately or substantially formed in the shape of a rectangle with two small sides being curved.

In order to effectively transmit rotating torque of the driving motor 30 to the rotary shaft 20 and the rotary tub 12 through the disk-shaped base 41 of the rotor 40, a reinforcing member 50 is attached to the outer surface of the base 41.

The reinforcing member 50 is formed in the shape of a disk. At the center of the reinforcing member 50 is formed a through-hole 51 having the same shape and size as the insertion hole 44 of the rotor 40, through which the inserting protrusion 21 of the rotary shaft 20 is inserted.

At the edge of the reinforcing member 50 are formed a plurality of fitting protrusions 52, which vertically extend, such that the reinforcing member 50 is easily attached to the base 41 of the rotor 40. At the base 41 of the rotor 40 are formed a plurality of fitting holes 47, into which the fitting protrusions 52 of the reinforcing member 50 are fitted.

When the fitting protrusions 52 of the reinforcing member 50 are fitted into fitting holes 47 of the base, respectively, from the outside of the rotor 40, the reinforcing member 50 is easily attached to the outer surface of the rotor 40 while the through-hole 51 of the reinforcing member 50 is aligned with the insertion hole 44 of the base 41.

The reinforcing member 50 is attached to the rotor 40, as described above, such that the strength of the disk-shaped base 41 of the rotor 40 is increased, whereby the rotary shaft 20 and the rotary tub 12, which are much heavier than the rotor 40, are smoothly rotated by the rotor 40.

In order to more stably fix the rotor 40 and the reinforcing member 50 to the rotary shaft 20, a fixing bolt 53 is threadly coupled into the rotary shaft 20 through the through-hole 51 of the reinforcing member 50 and the insertion hole 44 of the rotor 40 from the outside of the reinforcing member 50. Between the head of the fixing bolt 53 and the reinforcing member 50 is disposed a pad 54.

The pad 54 has a size larger than the through-hole 51 of the reinforcing member 50 and the insertion hole 44 of the rotor 40. Consequently, the head of the fixing bolt 53 presses the pad 54, as the fixing bolt 53 is threadly coupled into the rotary shaft 20, and therefore, the rotor 40 and the reinforcing member 50 are securely fixed to the rotary shaft 20.

Alternatively, the inserting protrusion 21 of the rotary shaft 20 may be forcibly fitted into the through-hole 51 of the reinforcing member 50 through the insertion hole 44 of the rotor 40, and the fitting protrusions 52 of the reinforcing member 50 may be forcibly fitted into the fitting holes 47 of the base 41 of the rotor 40, respectively. In this case, the fixing bolt 53 and the pad 54 are not necessary.

When the inserting protrusion 21 of the rotary shaft 20 is inserted through the insertion hole 44 formed at the center of the base 41 of the rotor 40, and the fitting protrusions 52 of the reinforcing member 50 are fitted into the corresponding fitting holes 47 of the base 41 from the outside of the rotor 40, as shown in FIGS. 4 and 5, the inserting protrusion 21 of the rotary shaft 20 is inserted through the through-hole 51 of the reinforcing member 50.

Subsequently, the fixing bolt 53 with the pad 54 fitted thereon is threadly coupled into the rotary shaft 20 through the through-hole 51 and the insertion hole 44 from the outside of the reinforcing member 50. As a result, the rotor 40 and the reinforcing member 50 are securely fixed to the rotary shaft 20. When the driving motor 30 is operated in this state, the rotor 40, whose strength is increased by the reinforcing member 50, is rotated, and therefore, the rotary shaft 20 and the rotary tub 12 are smoothly rotated.

As apparent from the above description, the rotor of the driving motor is directly connected to the rotary shaft. Consequently, the present invention has the effect of reducing manufacturing costs and assembling time. Also, the rotor is coaxially fixed to the rotary shaft, and therefore, noise and vibration are not generated when the rotor and the rotary shaft are rotated.

Furthermore, the strength of the rotor at the position where the rotor is fixed to the rotary shaft is increased by the reinforcing member that is easily attached to the rotor, and therefore, the rotary shaft and the rotary tub are smoothly rotated by the rotor.

Although exemplary embodiments of the present invention has been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents. 

1. A washing machine comprising: a water tub; a rotary tub disposed in the water tub; a rotary shaft which is mounted to the rotary tub and extends through the water tub; a rotor directly connected to an end of the rotary shaft; and a reinforcing member attached to the rotor which increases the strength of the rotor.
 2. The washing machine according to claim 1, wherein the rotor has a polygonal insertion hole, and the rotary shaft has a polygonal inserting protrusion formed at the end thereof, the inserting protrusion of the rotary shaft being inserted through the insertion hole of the rotor.
 3. The washing machine according to claim 2, wherein the reinforcing member has a polygonal through-hole corresponding to the insertion hole of the rotor, the inserting protrusion of the rotary shaft being inserted through the through-hole of the reinforcing member.
 4. The washing machine according to claim 2, wherein the reinforcing member has a plurality of fitting protrusions which extend vertically from the reinforcing member, and the rotor has a plurality of fitting holes, into which the fitting protrusions of the reinforcing member are fitted, respectively, such that the reinforcing member is easily attached to the rotor.
 5. The washing machine according to claim 1, further comprising: a fixing bolt threadly coupled to the inserting protrusion of the rotary shaft through the reinforcing member and the rotor from outside of the rotor.
 6. The washing machine according to claim 5, further comprising: a pad disposed between the reinforcing member and a head of the fixing bolt.
 7. The washing machine according to claim 1, further comprising: a stator mounted to an outer surface of the water tub while the stator is opposite to the rotor.
 8. A washing machine comprising: a water tub; a rotary tub disposed in the water tub; a rotary shaft mounted to the rotary tub while extending through the water tub; and a driving motor disposed at an outside of the water tub to rotate the rotary shaft, the driving motor comprising, a stator mounted to an outer surface of the water tub; a rotor disposed opposite to the stator; and a reinforcing member attached to the rotor to increase the strength of the rotor, the rotor having an insertion hole formed in a shape to prevent the rotor from rotating relative to the rotary shaft, and the rotary shaft having an inserting protrusion formed in a shape corresponding to that of the insertion hole, the inserting protrusion being inserted through the insertion hole, such that the rotary shaft is rotated along with the rotor.
 9. The washing machine according to claim 8, wherein the insertion hole of the rotor and the inserting protrusion of the rotary shaft are substantially formed in the shape of a rectangle.
 10. The washing machine according to claim 8, wherein the reinforcing member has a through-hole formed in a shape corresponding to the insertion hole of the rotor such that the reinforcing member is fixed to the rotary shaft.
 11. The washing machine according to claim 10, wherein the reinforcing member has a plurality of fitting protrusions protruded from an edge of the reinforcing member, and the rotor has a plurality of fitting holes, into which the fitting protrusions of the reinforcing member are fitted, respectively.
 12. The washing machine according to claim 10, further comprising a fixing bolt threadly coupled to the inserting protrusion of the rotary shaft through the reinforcing member and the rotor from outside of the rotor.
 13. The washing machine according to claim 12, further comprising a pad disposed between the reinforcing member and a head of the fixing bolt. 